Abstract: Based on survey data collected in March and June of 2012 , the status of fish community structure in 5 sampling stations of downstream of Jiuxian River in the west of Fujian were analyzed. The results showed that the captured 31 fishe species belonged to 9 families of 3 orders. Mastacembelus armatus was the protected fish of Fujian Province and Tilapia sp. was the alien species. Fish community through IRI indexes were anaylazed, Pesudobagrus fulvidraco、Cyprinus carpio、Acrossocheilus wenchowensis and Erythroculter ilishaeformis were the dominant species . The ecological types of the fish were consisted of mid-down fishes,omnivorous fish and the fish adapting to lentic or slow current waters mainly.Three diversity indexes which were Shannon-Wiener diversity index(H), Margalef diversity index(J), Evenness index(E) were used to analyze the characteristics of species diversity. Shannon-Wiener diversity index in Jitou village was higher than that in other 4 stations and fish community structure in Jitou Village was more stabilized. The fish community of dongstream Jiuxian River could be distinguished as two cluster，one was Jitou -Jiuzhou village cluster, the other was Yaofu,Shizhen and Meixi village cluster.To protect the fish diversity and decrease negative impact on it, some suggestions on the sustainable use of fishery resource in Jiuxian River were proposed.